Vertical blade play on sebenza? - Update

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kaosu04

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Apr 26, 2005
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Tried doing a search and the few threads I found on this aren't quite clear. I have a large 21 that has about a 75% lock up (I understand this is normal). There is no lateral blade play whatsoever, even with the action smooth as glass. However when it's locked and I try to move it in the vertical (between stop pin and lock) I can feel movement. Now when I say I can feel movement I'm not sure 100% sure it's the blade. But something is moving. I would not characterize this as looseness. Technically this could be the blade bushing, correct? When locked open movement should not be possible as the nature of the lock would take up any slack, but it's reasonable to believe that the blade bushing would not have a great amount of tension on it, and one could flex the lock while moving the blade to get the blade bushing to feel like something is not right.

I realize this isnt 100% normal. My brand new small does not do this whatsoever, but the large is several years old. I might end up sending it in, but I go out of town on the 1st of may for a year and not sure I want to risk not being able to bring it with me.

Anyone care to explain whether my reasoning is correct, and if this could possibly be typical of very well used sebenzas? I'm asking purely out of curiosity. It seems a very minor issue if an issue at all, so I'm not concerned. Just curious.
 
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I haven't experienced what you're describing. If you don't have time to send it in before you leave, I'd suggest doing a thorough cleaning yourself to see if it remedies the problem. Though, I suspect you'll have to send it in to be sure.
 
Is it assembled correctly....? Everything tightened down properly....? I am sure you checked all of these, but its these little things that can wreck havoc on any frame lock not functioning properly. If you have thoroughly went over everything and its good, perhaps the lockbar needs re-heat treated by CRK. I know its a PITA to send in, but sometimes you have too.

I know one time when I spoke to Chris, he said he would get nasty calls and emails saying their sebenza was not working....lol. He would have them send it in and it would be so filled with picket lint and other contamination that you could hardly open and close it. A simple cleaning made it good as new. I am NOT saying this is you in any way, just a point that contamination can cause opening and lockup issues.
 
my small 21 doesn't have vertical but a tiny bit of side to side play!
the knife has been a user since i got it but it is bugging me a bit:(
shall i send it in?
 
Nyefmaker,

Agreed in full on the up and down play.

OP, break it down, clean it, and re-assemble, ensuring that all screws are tighted down to the point that you hear an audible "pop" when you un-tighten. Your Allen wrench should have just a bit of flexion along the long portion (short portion in screwhead) when tightened down properly. If lockup is as you've described, and the lockbar is within specs, there should be no blade play.

The blasted ti surface of the slabs "locks" the blade bushing and stop pin sleeve into place, creating three total points of contact: the lockbar surface/blade tang, the blade tang/stop pin, and the bushing/blade bushing hole. All "micro-slop" as it were should be removed when, if again, everything is within specs, your knife is locked open. The stop pin and lockbar surface are in effect "jamming" the blade upward, removing the micro-slop.

My guess is, you may have some lint in one of the mating surfaces, or your lockbar flexion is not within specs.

Try the cleaning and re-assembling and let us know if that does the trick.

Prof.
 
The assembly is correct. This happens even after a fresh cleaning and assembly. The lockbar does feel weak in comparison to my small (taking into account the longer leverage as well). Maybe I'll just send it in and hope it gets back before may.
 
When locked open, if you push the lockbar just a bit toward the other handle, does it remove the slop?
 
PS to my last post, if this is the case, and putting pressure on the lockbar removes the slop, check to see if when you disassemble your knife that the lockbar is flexed beyond the point at which it is when assembled and locked open. It should be slightly beyond (roughly 50% beyond) the point where it is when it's together and locked open. If not, then you're lockbar is not engaging optimally because it is not properly tensioned.
 
How hard are you flexing the blade when this happens?

I ask because some people really bear down on the tip of the knife, thereby causing flexing, in any pocket knife there will be some blade play when this is done.

I am not saying you are doing this, but just want to make sure all basis are covered.
 
did you buy this knife used or new when you first got it? maybe there was a switch in the blade, and therefore, not a proper fit? one suggestion to add
 
Ps. Mine had similar problems, but that was after a 3meter fall resulting in the screws coming loose. I just kept using her and the problem went away. Sending it in from South Africa is not something I can easily do.

Ti is a forgiving and somewhat self healing material, but if it needs to be sent in it is better to do it.
 
It does remove the slop if push the lockbar in while moving the blade back and forth. This increases the lockup by about 10% and makes it stick when I try to disengage it. When disassembled the lockbar does move in about 50%. The locking surface almost clears the handle. The slop requires minimal force, but deliberate to cause the slop. I did buy the knife used.
 
Kao,

If you are concerned about it and have verified all is tightened properly/cleaned from your perspective, more than likely there is nothing else you can do yourself except worry at this point, just send it in :).
You might want to email ahead and ask what the normal turn around would be with their current workoad.
Hang in there!
 
Is it common for the lockbars to lose tension? I would think it's inevitable that they need to be re treated and that this is included under warranty work. After all, no spring can stay at it's original tension
 
Update
So as explained in my last post I ended up sending it in. I got it back on friday. I was told the play is caused by excessively forceful openings (being flicked open). I don't flick open any of my knives, but this particular sebbie I got used. So there's no telling what the previous owner did. The lockbar was re heat treated. The play is still there, but I've been told abuse of the knife is what caused it and replacement of the whole locking slab is the only way to get rid of it. I did get the pleasure of speaking to Mr. Reeve personally and he reassured me that the play is nothing to worry about it, and will only be worsened by further abuse. The heat treat did bring the lock up to about 50-60% when it was more like 70-80% when I sent it in. The blade was sharpened. The handles were re-blasted free of charge. I actually didnt even know they would be re-blasted until I saw it. At first I thought both slabs were replaced.
My overall impressions - I am extremely satisfied. I won't deny that the knife was most likely abused in a previous life, so I certainly dont expect any abuse, known or unknown to be fixed for free under warranty. I am happy that he still decided to work on the knife and re heat treat it even with obvious signs of negligence. And the bead blasting of the handles was quite the surprise gift. A lot of people here get to speak to Mr. Reeve personally, and it really shows a great dedication for the owner of any company to patiently spend time explaining anything at all to customers. I've been a CRK lover ever since I got my first sebenza. This is my first time sending something in for service and I'm impressed with the level of service. I now understand why the money doesn't just buy you one of the best knives you can get your hands, but a customer service experience that very few can beat.
 
This all of a sudden turned into a concern of mine. I just sent mine in and they did exactly what you had done to yours for the same issue.

I hope to hell I didnt just pay for a full spa treatment and fixing of the lock, and have the issue still there when I get it back.

This is why I buy crks, so that there is no blade play at all. Whats a crk with blade play?...................... Its a bradley alias! and i certainly as hell dont want one of those :(

Anyways Ill be getting it in the mail within the next couple of days and I hope all is fixed with mine.
 
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